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61.
We conducted three types of short beam shear tests of western hemlock (Tsuga heterophylla Sarg.) under various span/depth ratios, and examined whether the maximum shear stress was used as the shear strength. The following results were obtained. (1) In the short beam shear tests under the three-point loading method, it was difficult to have the specimen failing by horizontal shear. We thought that this method should not be recommended for determining the shear strength of wood. (2) In the short beam shear tests under the asymmetric four-point loading of the specimen with a rectangular cross-section, the failure caused by horizontal shear occurred under some span/depth ratio range. Nevertheless, this range was dependent on the specimen geometry and was quite restricted. We therefore think that this method should not be recommended for determining the shear strength of wood. (3) In the short beam shear tests under the asymmetric four-point loading of the I-shaped specimen, failure caused by horizontal shear occurred under the span/depth ratio range wider than that applicable for the asymmetric four-point loading of the specimen with a rectangular cross-section. The maximum shear stress was stable in a certain span/depth ratio range and the value of the maximum shear stress is effective as a parameter for comparing the shearing strength of materials with each other. 相似文献
62.
Tsutomu Suzuki Kyoko Suzuki Yukio Takahashi Mitsuhiro Okimoto Tetsuo Yamada Noriyasu Okazaki Yuichi Shimizu Masashi Fujiwara 《Journal of Wood Science》2007,53(1):54-60
Japanese larch wood loaded with nickel (1%–4%) alone or with nickel and calcium (0.25%–1.5%) was carbonized at 800°–900°C
for 0–120min with a heating rate of 5°–20°C min−1 in a helium flow of 5.8−46.4 ml STP cm−2 min−1 to examine the influence of these variables on the crystallization of carbon (the formation of T component) and the development
of mesoporosity. From the obtained results, reaction conditions suitable for effective production of carbon with the dual
functions of adequate electroconductivity and adsorption capacity in liquid phase were established, thereby explaining the
factors that govern the process. It was also confirmed that mesopore having a diameter of about 4 nm was selectively produced
at the cost of specific (BET) surface area in parallel with the formation of T component. This result provided good insight
into how the simultaneous dual function could be realized. 相似文献
63.
Hirobe Muneto Sabang John Bhatta Balram K. Takeda Hiroshi 《Journal of Forest Research》2004,9(4):341-346
In a lowland tropical rain forest in Sarawak, leaf-litter decomposition and the initial litter chemistry of 15 tree species
were studied. During 13 months of field experiment, weight loss of litter samples was between 44% and 91%, and calculated
decomposition rate constants (k) ranged from 0.38 to 2.36 year−1. The initial litter chemistry also varied widely (coefficients of variation: 19%–74%) and showed low N and P concentrations
and high acid-insoluble residue (AIS) concentration. For nutrient-related litter chemistry, correlations with the decomposition
rate were significant only for P concentration, C/P ratio, and AIS/P ratio (r
s
= 0.59, −0.62, and −0.68, n = 15, P < 0.05, respectively). For organic constituents, correlations were significant for concentrations of AIS and total carbohydrates,
and AIS/acid-soluble carbohydrate ratio (r
s
= −0.81, 0.51, and −0.76, n = 15, P < 0.05, respectively). These results suggested that the relatively slow mean rate of decomposition (k = 1.10) was presumably due to the low litter quality (low P concentration and high AIS concentration), and that P might influence
the decomposition rate; but organic constituents, especially the concentration of AIS, were more important components of initial
litter chemistry than nutrient concentrations. 相似文献
64.
Rei NAKANO Kazuya EDAMURA Tomohiro NAKAYAMA Kenji TESHIMA Kazushi ASANO Takanori NARITA Ken OKABAYASHI Hiroshi SUGIYA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(1):27-35
We investigated the in
vitro differentiation of canine bone marrow stromal cells (BMSCs) into voltage-
and glutamate-responsive neuron-like cells. BMSCs were obtained from the bone marrow of
healthy beagle dogs. Canine BMSCs were incubated with the basal medium for neurons
containing recombinant human basic fibroblast growth factor (bFGF; 100
ng/ml). The viability of the bFGF-treated cells was
assessed by a trypan blue exclusion assay, and the morphology was monitored. Real-time
RT-PCR was performed to evaluate mRNA expression of neuronal, neural stem cell and glial
markers. Western blotting and immunocytochemical analysis for the neuronal markers were
performed to evaluate the protein expression and localization. The Ca2+
mobilization of the cells was evaluated using the Ca2+ indicator Fluo3 to
monitor Ca2+ influx. To investigate the mechanism of bFGF-induced neuronal
differentiation, the fibroblast growth factor receptor inhibitor, the phosphoinositide
3-kinase inhibitor or the Akt inhibitor was tested. The bFGF treatment resulted in the
maintenance of the viability of canine BMSCs for 10 days, in the expression of neuronal
marker mRNAs and proteins and in the manifestation of neuron-like morphology. Furthermore,
in the bFGF-treated BMSCs, a high concentration of KCl and L-glutamate induced an increase
in intracellular Ca2+ levels. Each inhibitor significantly attenuated the
bFGF-induced increase in neuronal marker mRNA expression. These results suggest that bFGF
contributes to the differentiation of canine BMSCs into voltage- and glutamate-responsive
neuron-like cells and may lead to the development of new cell-based treatments for
neuronal diseases. 相似文献
65.
Mariko TAKAYASU Kouko HAMAMOTO Hiroshi SATOH Toshihiro ICHIJO Toru TAKAHASHI Kazuhisa FURUHAMA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(2):261-263
To clarify the effect of renal dysfunction on pharmacokinetics of the prokinetic agent metoclopramide (MCP), we administered intravenously 0.4 mg/kg MCP to healthy calves and calves subjected to right kidney vessel ligation (ligation) without or with a subsequent left nephrectomy (ligation plus removal). Plasma MCP concentration, glomerular filtration rate (GFR) and plasma prolactin level were measured by liquid chromatography-tandem mass spectrometry, simplified equation using iodixanol and enzyme-linked immunosorbent assay, respectively. Only in calves with ligation plus removal, plasma MCP concentrations were increased significantly 6, 8 and 12 hr after injection, showing that a negative correlation was observed between the plasma MCP concentrations and GFR value. A tendency to increase in plasma PRL concentration was noted also in these calves. In conclusions, plasma MCP concentrations depend on the GFR mode in calves, and its critical GFR value was estimated. 相似文献
66.
Toyokazu KOBAYASHI Hiroshi KOIE Arisa WATANABE Arisa INO Kazuya WATABE Mujo KIM Kiichi KANAYAMA Kazuya OTSUJI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(4):503-506
We examined the effects of chicken egg hydrolysate (also known as “bone peptide” or BP)
on bone metabolism in 5- to 8-month-old orchidectomized dogs. The bone formation marker
serum bone alkaline phosphatase (BAP) and the bone resorption marker urine
deoxypyridinoline (DPD) were used as indicators to measure changes in bone metabolism. The
following results were observed that Serum BAP was higher in dogs fed BP-enriched food
throughout the clinical investigation. Serum BAP was statistically significantly higher in
dogs fed BP-enriched food than in dogs fed non-BP-enriched food at 2 months after
orchidectomy. This suggests that BP promoted bone formation immediately after
orchidectomy. 相似文献
67.
Nobukazu SAISHU Kazutaka MORIMOTO Hiroshi YAMASATO Hiroichi OZAKI Toshiyuki MURASE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(9):1037-1042
Thirty-eight Aerococcus viridans isolates were obtained from milk from
478 cows with clinical mastitis in a farm during the periods between November 2011 and
February 2012, and between December 2012 and March 2013. Additional isolates were obtained
from processed manure (a mixture of composted manure, straw and hydrated lime) and bedding
materials. The processed manure was later used to cover the floor of the stalls in barns
as bedding materials. The temperatures recorded in the composted and processed manure were
not as high as those generally observed during satisfactory composting. To reveal the
association of A. viridans in manure-related products with intramammary
infection in cows, isolates were characterized by their DNA fragment patterns as
determined by pulsed-field gel electrophoresis (PFGE) and antimicrobial susceptibility
testing. Isolates obtained from milk, processed manure and bedding materials had identical
DNA fragment patterns. Antimicrobial susceptibilities were determined for 29 isolates from
milk, processed manure and bedding materials. Of these, 26 (89.7%) were resistant to
clindamycin, whereas virtually all the isolates were susceptible to 12 other
antimicrobials including cefalosporins that have been used to treat bovine mastitis in
Japan. In vitro, three A. viridans isolates from milk
and an isolate from processed manure survived for 3 hr in Good’s buffer (pH 9) at high
temperature (50°C). The results suggest that the processed manure and bedding materials in
this farm were possible sources of A. viridans that caused infection in
the cows with mastitis. 相似文献
68.
Weak activity of UDP-glucuronosyltransferase toward Bisphenol analogs in
mouse perinatal development
Risa YABUSAKI Hidetomo IWANO Sumito TSUSHIMA Nanako KOIKE Naoko OHTANI Kentaro TANEMURA Hiroki INOUE Hiroshi YOKOTA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(11):1479-1484
Bisphenol A (BPA) is a widely used industrial chemical that disrupts endocrine function.
BPA is an endocrine disrupting chemical (EDC) that has been demonstrated to affect
reproductive organ development, brain development, metabolic disease and post-natal
behavior. Accordingly, Bisphenol analogs, Bisphenol F (BPF, bis (4-hydroxyphenyl) methane)
and Bisphenol AF (BPAF, 4,4-hexafluoroisopropylidene) diphenol) are used as replacements
for BPA. BPA is mainly metabolized by UDP-glucuronosyltransferase (UGT), UGT2B1, but this
effective metabolizing system is weak in the fetus. In the present study, we demonstrated
that hepatic UGT activity toward BPAF was very weak, in comparison with BPA and BPF, in
the fetus, pups and dams. Conversely, hepatic UGT activity toward BPF was very weak in the
fetus and newborn pups, and was increased to the same level as BPA post-partum. In
conclusion, BPAF possibly tends to accumulate in the fetus, because of weak metabolism
during the perinatal period, suggesting that the metabolism of individual Bisphenol
analogs requires assessment to properly gauge their risks. 相似文献
69.
Hiroshi ISEKI Michihiro TAKAGI Kenji KAWASHIMA Tomoyuki SHIBAHARA Yoshiko KURODA Hiroshi TSUNEMITSU Makoto YAMAKAWA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(12):1663-1666
To clarify the pathogenicity of Japanese type 1 porcine reproductive and respiratory
syndrome virus (PRRSV) isolate in experimentally infected pigs, we evaluated clinical
signs and monitored viremia for 21 days post-inoculation (dpi). Lungs were mottled, tanned
and reddish in appearance; had lesions predominantly in the cranial, middle and accessory
lobes; and failed to collapse at 10 dpi. Although microscopic lesions of lungs were
reproduced using the Japanese emerging type 1 PRRSV isolate under experimental conditions,
no significant differences were noted between the challenge and control groups regarding
mean rectal temperature and daily weight gain. These results provide useful insights into
the limited pathogenicity of single infection with the Japanese type 1 PRRSV isolate in
piglets, which differ from findings in reported field cases. 相似文献
70.
Mitigation of nitrous oxide (N2O) emission from swine wastewater treatment in an aerobic bioreactor packed with carbon fibers
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Takahiro Yamashita Ryoko Yamamoto‐Ikemoto Hiroshi Yokoyama Hirofumi Kawahara Akifumi Ogino Takashi Osada 《Animal Science Journal》2015,86(3):358-368
Mitigation of nitrous oxide (N2O) emission from swine wastewater treatment was demonstrated in an aerobic bioreactor packed with carbon fibers (CF reactor). The CF reactor had a demonstrated advantage in mitigating N2O emission and avoiding NOx (NO3 + NO2) accumulation. The N2O emission factor was 0.0003 g N2O‐N/gTN‐load in the CF bioreactor compared to 0.03 gN2O‐N/gTN‐load in an activated sludge reactor (AS reactor). N2O and CH4 emissions from the CF reactor were 42 g‐CO2 eq/m3/day, while those from the AS reactor were 725 g‐CO2 eq/m3/day. The dissolved inorganic nitrogen (DIN) in the CF reactor removed an average of 156 mg/L of the NH4‐N, and accumulated an average of 14 mg/L of the NO3‐N. In contrast, the DIN in the AS reactor removed an average 144 mg/L of the NH4‐N and accumulated an average 183 mg/L of the NO3‐N. NO2‐N was almost undetectable in both reactors. 相似文献